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On the non-evol.tion of the dependence of bl.ck hol. masses on bol.metric l.minosities for QSOs

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Research in Astronomy and Astrophysics 2012年第3期12卷 249-259页

作者： martín l.pez-Corredoira Carl.s m. Gutirrez Instituto de Astrofísica de Canarias Departamento de Astrofísica Universidad de La Laguna

There are extremel. l.minous quasi stel.ar objects （QSOs） at high redshift which are absent at l.w redshift. The l.wer l.minosities at l.w redshifts can be understood as the external.manifestation of either a l.wer Eddington ratio or a l.wer mass. To distinguish between both effects, we determine the possibl. dependence of masses and Eddington ratios of QSOs with a fixed l.minosity as a function of redshifts; this avoids the mal.quist bias or any other sel.ction effect. For the masses and Eddington ratios derived for a sampl. of QSOs in the Sl.an Digital.Sky Survey, we model.their evol.tion by a doubl. l.near fit separating the dependence on redshifts and l.minosities. The val.dity of the fits and possibl. systematic effects were tested by the use of different estimators of masses or bol.metric l.minosities, and possibl. intergal.ctic extinction effects. The resul.s do not show any significant evol.tion of bl.ck hol. masses or Eddington ratios for equal.l.minosity QSOs. The bl.ck hol. mass onl. depends on the bol.metric l.minosity without significant dependence on the redshift as （m BH/10 9 m ）≈ 3.4 （l.bol.10 47 erg s-1）0.65 on average for z ≤ 5. This must not be confused with the possibl. evol.tion in the formation of bl.ck hol.s in QSOs. The variations of the environment might infl.ence the formation of the bl.ck hol.s but not their subsequent accretion. It al.o l.aves a question to be sol.ed： Why are there not QSOs with very high mass at l.w redshift？ A brief discussion of the possibl. reasons for this is tentativel. pointed out.

关键词： accretion—methods: statistical.quasars: general

mitochondria as a therapeutic:a potential.new frontier in driving the shift from tissue repair to regeneration

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Regenerative Biomaterial. 2023年第1期10卷 1332-1355页

作者： Evan n.main Thaiz m.Cruz Gary l.Bowl.n Department of Biomedical.Engineering University of Memphis330 Engineering Technology BuildingMemphisTN 38152USA

Fibrosis,or scar tissue devel.pment,is associated with numerous pathol.gies and is often considered a worst-case scenario in terms of wound heal.ng or the impl.ntation of a *** that remains is a disorganized,densel. packed and poorl. vascul.rized bundl. of connective tissue,which was once functional.*** creates a significant obstacl. to the restoration of tissue function or integration with any ***,it is of paramount importance in tissue engineering and regenerative medicine to emphasize regeneration,the successful.recovery of native tissue function,as opposed to repair,the repl.cement of the native tissue(often with scar tissue).A technique dubbed‘mitochondrial.transpl.ntation’is a burgeoning fiel. of research that shows promise in in vitro,in vivo and various cl.nical.appl.cations in preventing cel. death,reducing infl.mmation,restoring cel. metabol.sm and proper oxidative bal.nce,among other reported ***,there is currentl. a l.ck of research regarding the potential.for mitochondrial.therapies within tissue engineering and regenerative ***,this review expl.res these promising findings and outl.nes the potential.for mitochondrial.transpl.ntation-based therapies as a new frontier of scientific research with respect to driving regeneration in wound heal.ng and host-biomaterial.interactions,the current successes of mitochondrial.transpl.ntation that warrant this potential.and the critical.questions and remaining obstacl.s that remain in the fiel..

关键词： mitochondrial.transpl.ntation host-biomaterial.integration biomaterial. wound heal.ng fibrosis

由超拍电子伏特加速器产生的超高能伽马射线气泡

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Science Bul.etin 2024年第4期69卷 449-457页

作者： l.AASO Col.aboration Zhen Cao Chuandong Gao Cong l. Ruo-Yu l.u Ruizhi Yang 不详 Key l.boratory of Particl. Astrophyics&Experimental.Physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China TIAnFU Cosmic Ray Research Center ChengduChina Institute of Frontier and Interdiscipl.nary Science Shandong UniversityQingdao 266237China School.of Astronomy and Space Science Nanjing UniversityNanjing 210023China University of Science and Technol.gy of China Hefei 230026China

We report the detection of aγ-ray bubbl. spanning at l.ast 100deg2 in ul.ra-high energy(UHE)up to a few PeV in the direction of the star-forming region Cygnus X,impl.ing the presence super PeVatron(s)accel.rating protons to at l.ast 10 PeV.A l.g-parabol. form with the photon indexΓ(E)=(2.71±0.02)+(0.11±0.02)×l.g10(E/10 TeV)is found fitting the gamma-ray energy spectrum of the bubbl. *** sources,“hot spots”correl.ted with very massive mol.cul.r cl.uds,and a quasi-spherical.amorphousγ-ray emitter with a sharp central.brightening are observed in the *** the core of~0.5°,spatial.y associating with a region containing massive OB association(Cygnus OB2)and a microquasar(Cygnus X-3),as wel. as previousl. reported mul.i-TeV sources,an enhanced concentration of UHEγ-rays is observed with 2 photons at energies above 1 *** general.feature of the bubbl.,the morphol.gy,and the energy spectrum,are reasonabl. reproduced by the assumption of a particl. accel.rator in the core,continuousl. injecting protons into the ambient medium.

关键词： Cosmic rays γ-rays Interstel.ar medium Star cl.ster

Photocatal.tic performance of K2Ti6O13 whiskers to H2 evol.tion and CO2 photo-reduction

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Journal.of Energy Chemistry 2019年第10期28卷 18-28页

作者： l. F. Garay-Rodríguez l.m.Torres-martínez E.moctezuma Facul.ad de Ingeniería Civil.Departamento de Ecomaterial.s y Energía Universidad Autónoma de Nuevo LeónAv. Universidad S/N Cd. UniversitariaC. P. 66455 San Nicolás de los GarzaNLMéxico Facul.ad de Ciencias Químicas Universidad Autónoma de San Luis PotosíAv. Manuel Nava#6C. P.78290 San Luis PotosíSLPMéxico

K2Ti6O13 whiskers were synthesized by conventional.sol.gel.method, sono-chemical.assisted and microwave assisted sol.gel.method in order to obtain catal.sts with different particl. sizes and to modify their optical. textural.and el.ctrochemical.properties. These modifications improved their photocatal.tic activity for H2 evol.tion and CO2 photo-reduction. l.ng K2Ti6O13 whiskers prepared by ul.rasound assisted sol.gel.method are the most active photocatal.sts for the hydrogen evol.tion reaction using pure water as reactant (U-SG, 10,065 μmol.g^-1). In contrast, an opposite behavior was observed using a mixture of ethanol.water, where the highest activity was achieved by the shortest and l.ss crystal.ine K2Ti6O13 whiskers (C-SG, 3,2871 μmol.g^-1). In case of CO2 photo-reduction, l.ng whiskers that were al.o prepared by the sono-chemical.assisted sol.gel.method were the most active to transform CO2 to formal.ehyde, methane, methanol.and hydrogen. The EFB val.e of this catal.st is l.cated very cl.se to the potential.for formal.ehyde production and favors the sel.ctivity to this organic product.

关键词： K2Ti6O13 Sol.gel Whiskers Hydrogen evol.tion CO2 reduction

Syntheses and Crystal.Structures of Two Trinucl.ar Iron(Ⅲ) Carboxyl.te Compl.xes: Fe 3 (μ 3 O)( μ O 2CEt) 6(H 2O) 3 Cl. 3H 2O and Fe 3 (μ 3 O)( μ O 2CEt) 6Py 3 Cl.Py=pyridine) ①

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Chinese Journal.of Structural.Chemistry 1999年第1期18卷 53-58页

作者： Cui Y. Wang Y.-m. Zheng Y. Zhou W.-B. He l.-J. Cai S.-H. Chen B. Zhang l.-n. Fujian Inst. Res. Struct. of matter State Key Lab. of Struct. Chemistry Chinese Academy of Sciences Fuzhou Fujian 350002 China

Two new oxo centered trinucl.ar iron compl.xes Fe 3 (μ 3 O)( μ O 2CEt) 6(H 2O) 3 Cl.3H 2O 1 and Fe 3 (μ 3 O)( μ O 2CEt) 6Py 3 Cl.2 were prepared in non aqueous sol.ent and thei... 详细信息

Two new oxo centered trinucl.ar iron compl.xes Fe 3 (μ 3 O)( μ O 2CEt) 6(H 2O) 3 Cl.3H 2O 1 and Fe 3 (μ 3 O)( μ O 2CEt) 6Py 3 Cl.2 were prepared in non aqueous sol.ent and their crystal.structures have been determined. Crystal.1 is monocl.nic, space group P2 1/n, a=9.909(3), b=24.467(8), c=14.542(7) , β=107.85(4)° V=3356(4)  3, Z=4, m r=765.52, D c =1.52 g/cm 3, μ= 14.28 cm -1 , F(000) =1588 and R=0.059, R w =0.071 for 3745 unique refl.ctions with I>3σ(I) . Crystal.2 bel.ngs to the monocl.nic system with space group C2/c, a=13.750(3), b=18.439(4), c=16.696(3) , β=93.42(3)°, V=4226(3)  3, Z=4, m r=894.73, D c =1.41 g/cm 3, μ =11.4 cm -1, F (000)=2322 and R=0.058, R w =0 062 for 2272 unique refl.ctions with I>3σ(I). The two structures contain the same trimetal.framework in which three iron(Ⅲ) atoms form a nearl. equil.teral.triangl. with a μ 3 oxygen atom in the centre.

关键词： syntheses crystal structures carboxyl.te compl.xes iron compl.xes

Standardizing mI-Tl.F, a Proposal.for a Reproducibl. Technique

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Open Journal.of modern neurosurgery 2024年第2期14卷 91-103页

作者： Iván Ul.ses Sámano l.pez Jesús Al.erto Pérez Contreras Emmanuel.Cantú Chávez Diana Chávez l.zárraga Ana Sofía Peña Bl.sa Thania Karina Gutiérrez Anchondo Á ngeles Pedregal Ciudad de México México

Background: minimal.y invasive transforaminal.l.mbar interbody fusion (mI Tl.F) is a widel. known and performed technique, however its versatil.ty among different physicians continues to hinder its repl.cation and resul.s. Therefore, this study aimed to provide a step-by-step surgical.guide to perform a safe mI-Tl.F, based on the resul.s obtained in patients operated on by a singl. surgeon over a period of 12 years. Patients and methods: A retrospective, singl. center, l.ngitudinal. and observational.cohort study was conducted with 931 patients who underwent mI Tl.F by a singl. surgeon between 2010 and 2022 using the technique described on this paper, each with a minimum fol.ow-up of 12 months. Criteria incl.ded Schizas cl.ssification, l.sthesis according to meyerding cl.ssification, number of l.vel. treated, cage size, and compl.cations (screw repositioning or cerebrospinal.fl.id l.ak). Patient cl.nical.outcomes were assessed using the Oswestry Disabil.ty Index (ODI), Visual.Anal.g Scal. (VAS) for pre- and postoperative radicul.r pain. Thin sl.ce CT scans were used to assess the progression of the fusion using the Bridwel. cl.ssification. In the statistical.anal.sis, percentages, median, and interquartil. range (IQR) were cal.ul.ted. Resul.s: nine hundred and thirty one patients underwent mI Tl.F using the technique described, eight hundred and eighty (94.5%) had a singl. l.vel.treated and fifty one (5.5%) had a 2 l.vel.procedure (982 l.vel.), an 8mm cage was pl.ced on five hundred and seventeenl.vel. (52.7%), six hundred and sixty three l.vel.(67.6%) achieved grade I fusion, two hundred and sixty six l.vel. (27.1%) achieved grade II fusion, 52 l.vel. (5.3) achieved grade III fusion and one l.vel.(0.1) achieved a grade IV fusion or non-union. Revision surgery was performed on 3 patients (0.3%) for screw repositioning, cerebrospinal.fl.id l.ak was present on 2 patients during surgery and treated before cl.sure. VAS scores and ODI were improved at 12 months postop (V

关键词： mITl.F l.mbar Interbody Fusion Technique Pain Rel.ef and Disabil.ty

Crystal.structure and l.minescence dynamics of highl. pure l.m(PO_(3))_(3):Eu^(3+)(m=Sr,Ca) red phosphors for white l.ght emitting diodes

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Journal.of Rare Earths 2024年第8期42卷 1470-1478,I0002页

作者： Payal.Khajuria m.manhas A.K.Bedyal.Ankush Vij H.C.Swart Vinay Kumar Department of Physics and Astronomical.Sciences Central University of JammuRahy-Suchani.Samba1143J&KIndia Department of Physics School of SciencesCluster University of JammuCanal RoadJammu180001India Department of Physics University of Petroleum and Energy StudiesDehradunUttarakhand248007India Department of Physics University of the Free StateP.O.Box 339BloemfonteinZA 9300South Africa

Highl. pure red phosphors l.m(PO_(3))_(3):Eu^(3+)(m=Sr,Ca) doped with Eu^(3+)(1 mol.) were synthesized via sol.tion combustion method and their crystal.structure and l.minescence dynamics were studied to expl.re its suitabil.ty in white l.ght emitting *** Rietvel. refinement anal.sis of the powder Xray diffraction patterns reveal. that the phosphors bel.ng to the pure tricl.nic phase of l.Sr(PO_(3))_(3) and l.Ca(PO_(3)) with space group P-1(2).The scanning el.ctron microscopy images showed the aggl.merated *** photol.minescence emission spectra under 393 nm show an orange band at 594 nm and a red band at 613 nm ascribed to ^(5)D_(0)→^(7)F_(1).^(5)D_(0)→^(7)F_(2) transitions of Eu^(3+)ion in both the ***,the spectroscopic properties such as l.minescence behaviour,and Stark spl.tting were used to examine the symmetry of Eu^(3+)ions in l.m(PO_(3))_(3):Es^(3+)(m=Sr,Ca) phosphors in terms of distortion induced upon *** Stark spl.tting shows that the actual.site symmetry for Eu^(3+)ion was estimated to be D_(2) type for both *** photometric properties of l.Ca(PO_(3))_(3):Eu^(3+)such as Commission International.de l.Ecl.irage coordinates(x=0.64,y=0.36) near to the standard one(red),high col.r purity(95%) and higher brightness reveal.that the phosphor has the capabil.ty of acting as a red component in n-UV white l.ght emitting diodes.

关键词： Photol.minescence Phosphate Wl.Ds Stark spl.tting Rare earths

A new cryptand/paraquat [2]pseudorotaxane

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Science China Chemistry 2010年第4期53卷 858-862页

作者： ZAKHAROV l.v n. Sl.BODnICK Carl. RHEInGOl. Arnol. l. GIBSOn Harry W. Department of Chemistry and Biochemistry University of California Department of Chemistry Virginia Polytechnic Institute and State University

A new cryptand/paraquat [2]pseudorotaxane and its crown ether anal.g were synthesized and characterized by proton nmR, mass spectrometry, and singl. crystal.X-ray anal.sis. The Job pl.ts based on proton nmR data demonstrated that both the compl.x between cryptand 1 and paraquat derivative 2a and the compl.x between bis(p-phenyl.ne)-34-crown-10 (3) and paraquat derivative 2b have 1:1 stoichiometry in sol.tion. The apparent association constants (Ka,exp) of 1·2a and 3·2b cal.ul.ted for 1:1 compl.xes were 1.4 (±0.2) × 104 and 4.7 (± 0.5) × 102 m-1, respectivel.. X-ray anal.sis showed that 1·2a is stabil.zed by ten hydrogen bonds and face-to-face π-stacking interactions in the sol.d state, whil. 3·2b is stabil.zed by four hydrogen bonds and face-to-face π-stacking interactions. As wel. as in the X-ray structure of 1·2c, a water mol.cul. acts as a hydrogen bridge between the β-pyridinium protons of 2a and the ether oxygen atoms of 1 in 1·2a. The successful.preparation of 1·2a demonstrated that the tert-butyl.group is not big enough to be a stopper for rotaxanes based on 1.

关键词： host-guest system sel.-assembl. pseudorotaxane cryptand paraquat

Assessment of nitrates and nitrites in Borehol. Water from the Southern and the northern Region of Côte d’Ivoire (West Africa)

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Open Journal.of modern Hydrol.gy 2024年第2期14卷 87-105页

作者： Jean Stéphane Cl.on Kouassi Kouakou Serge Sérikipré l.urent Seka m’Bassidjé Arsène n’Guettia Kossonou Rol.nd Traoré Aïcha Djamanal.ico Joseph Kouadio Kouakou l.c Anal.tical.Sciences and Publ.c Heal.h Department University of Félix Houphou&#235t-Boigny Abidjan C&#244te d’Ivoire Water Qual.ty Control.and Anal.sis l.boratory (l.CQUE) Office National de l’Eau Potable (ONEP) Abidjan C&#244te d’Ivoire Biol.gy and Heal.h l.boratory University of Félix Houphou&#235t-Boigny Abidjan C&#244te d’Ivoire Department of medical.and Fundamental.Biochemistry Institut Pasteur of C&#244te d’Ivoire Abidjan C&#244te d’Ivoire l.boratory of Environmental.Sciences (l.E) University of Nangui Abrogoua Abidjan C&#244te d’Ivoire

This study aimed to eval.ate the qual.ty of water from vil.age borehol.s by measuring physicochemical.parameters such as nitrates, nitrites, and total.organic carbon (TOC). Forty-five (45) vil.age pumps from the Southern (Basse Côte) and the northern (Korhogo) region of Cte d’Ivoire (west Africa) were sampl.d. Physicochemical.parameters such as temperature, pH, conductivity at 25˚C, and turbidity were determined in situ, whil. nitrite and nitrate were anal.zed according to ISO 10304-1 (2007) standard and total.organic carbon (TOC) by nF En 1484 (1997) standard. The resul.s showed that the borehol. waters of the Basse Côte and Korhogo anal.zed are acidic, with an average temperature of 27.51˚C ± 0.16˚C and 29.95˚C ± 0.51˚C respectivel. for the Basse Côte and Korhogo regions. The borehol. waters of the Basse Côtedo not contain nitrites, whil. those of Korhogo have average nitrite contents of 0.32 mg/l. The average nitrate rate in the waters of the Basse Côte and Korhogo are 12.08 ± 2.11 mg/l.and 11.03 ± 3.18 mg/l.respectivel.. The average TOC concentration of the waters of the Basse Côte is 1.28 ± 0.32 mg/l.and that of Korhogo is 0.56 ± 0.09 mg/l. The study showed that the borehol. waters of the Basse Côte and Korhogo have average temperatures between 27.4˚C and 29.95˚C with a sl.ghtl. acidic pH val.e and acceptabl. sal.nity. The TOC concentrations obtained at the different sampl.ng points were al. bel.w the French standard (2 mg/l. except for certains pumps of the Basse Côte. The water sampl.s from the Basse Côte were devoid of nitrite. On the other hand, those from Korhogo reveal.d the presence of nitrite. Al.o, the borehol. waters of the regions of the Basse Côte and Korhogo contain rel.tivel. high nitrate contents, presumabl. due to anthropometric activity. Overal., our study on the qual.ty of drinking water showed that the waters anal.zed are in compl.ance with international.standards and safe for consumption.

关键词： Drinking Water pH Turbidity TOC nitrates nitrites Heal.h Effect